Hey Kelly,
It sounds like you might well have anxiety issues. There are so many symptoms of anxiety, both physically and emotionally. I have mild to moderate anxiety issues and find myself worrying about pretty much the same things as you do. I recommend going and seeing you Doctor as soon as you can. In the mean time, perhaps when you're sitting at home, take a situation that makes you feel like that and work around it in your head. Try to answer questions like 'At what point do the emotional symptoms start to manifest?', then 'When do the physical signs show themselves?'. At each stage you begin to feel the symptoms, stop, take some deep breaths and then when you feel able go deep into the situation and when you start feeling worse, do it again. Pretty much a case of rinse and repeating those steps. It's worked with me in situations and now, as a team leader I find myself in a lot of 'stressful' situations and literally, no matter what I'm doing now, I stop, close my eyes, take some deep breaths and then act on the situation.
Let me know how things go!
The doc started me on amitriptyline a nasty but effective antidepressant. Two days later the issues resolved completely...such a relief.
You could have anxiety which can go hand in hand with depression (sometimes). Please see your GP, he may refer you to a psychiatrist. Suffering is not necessary.
Good luck.